ruby 文件操作

一、新建文件

 f=File.new(File.join("C:","Test.txt"), "w+")

 f.puts("I am Jack")

 f.puts("Hello World")

文件模式

"r" ：Read-only. Starts at beginning of file (default mode).

"r+" ：Read-write. Starts at beginning of file.

"w" ：Write-only. Truncates existing file to zero length or creates a new file for writing.

"w+" ：Read-write. Truncates existing file to zero length or creates a new file for reading and writing.

"a" ：Write-only. Starts at end of file if file exists; otherwise, creates a new file for writing.

"a+" ：Read-write. Starts at end of file if file exists; otherwise, creates a new file for reading and writing.

"b" ：(DOS/Windows only.) Binary file mode. May appear with any of the key letters listed above

二、读取文件

 file=File.open(File.join("C:","Test.txt"),"r")

 file.each { |line| print "#{file.lineno}.", line }

 file.close

三、新建、删除、重命名文件

 File.new( "books.txt", "w" )

 File.rename( "books.txt", "chaps.txt" )

 File.delete( "chaps.txt" )

四、目录操作

1创建目录

 Dir.mkdir("c:/testdir")

04#删除目录

05Dir.rmdir("c:/testdir")

07#查询目录里的文件

08p Dir.entries(File.join("C:","Ruby")).join(' ')

10#遍历目录

11Dir.entries(File.join("C:","Ruby")).each {

       |e| puts e

 }

1、ARGV and ARGF

ARGV

 ARGV << "cnblogslink.txt"

 #The gets method is a Kernel method that gets lines from ARGV

 print while gets

 p ARGV.class

ARGF

 while line = ARGF.gets

  print line

 end

2、文件信息查询

 #文件是否存在

 p File::exists?( "cnblogslink.txt" ) # => true

 #是否是文件

 p File.file?( "cnblogslink.txt" ) # => true

 #是否是目录

 p File::directory?( "c:/ruby" ) # => true

 p File::directory?( "cnblogslink.txt" ) # => false

 #文件权限

 p File.readable?( "cnblogslink.txt" ) # => true

 p File.writable?( "cnblogslink.txt" ) # => true

 p File.executable?( "cnblogslink.txt" ) # => false

 #是否是零长度

 p File.zero?( "cnblogslink.txt" ) # => false

 #文件大小 bytes

 p File.size?( "cnblogslink.txt" ) # => 74

 p File.size( "cnblogslink.txt" ) # => 74

 #文件或文件夹

 p File::ftype( "cnblogslink.txt" ) # => "file"

 #文件创建、修改、最后一次存取时间

 p File::ctime( "cnblogslink.txt" ) # => Sat Sep 19 08:05:07 +0800 2009

 p File::mtime( "cnblogslink.txt" ) # => Sat Sep 19 08:06:34 +0800 2009

 p File::atime( "cnblogslink.txt" ) # => Sat Sep 19 08:05:07 +0800 2009

3、查找文件

 puts "查找目录下所有文件及文件夹" 

 Dir["c:/ruby/*"].each {|x| 

       puts x

 } 

 puts "条件查询" 

 Dir.foreach('c:/ruby') { 

     |x| puts x if x != "." && x != ".."

 }

 puts "查找某一类型文件"

 Dir["*.rb"].each {|x| 

   puts x

  }

 puts "Open 查询"

 Dir.open('c:/ruby') { |d| d.grep /l/ }.each{|x| puts x}

 puts "---------------------------"      

 puts "正则表达式查询"

 Dir["c:/ruby/ruby/[rs]*"].each{|x| puts x} 

 puts "------------------------"

 Dir["c:/ruby/[^s]*"].each{|x| puts x}

 puts "------------------------"    

 Dir["c:/ruby/{ruby,li}*"].each{|x| puts x} 

 puts "------------------------"    

 Dir["c:/ruby/?b*"].each{|x| puts x}        

 puts "查找目录及子目录的文件"

 require 'find'     

 Find.find('./') { |path| puts path }